The HRF40A from Micross is a Space Qualified Diode with Dynamic Resistance 26 to 95 Degree C/W (Thermal), Forward Current 0.12 to 0.25 A, Forward Voltage 8 V, Reverse Current 1 to 10 uA, Reverse Voltage 4000 V. Tags: Axial-Lead. More details for HRF40A can be seen below.